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11.
An 81 year old right handed woman developed a left alien hand syndrome characterised by involuntary movements of choking and hitting the face, neck, and shoulder. The patient showed multiple disorders of primary sensation, sensory processing, hemispatial attention, and visual association, as well as a combination of sensory, optic, and cerebellar ataxia (triple ataxia) of the left arm in the absence of motor neglect or hemiparesis. Imaging studies disclosed subacute infarction in the right thalamus, hippocampus, inferior temporal lobes, splenium of corpus callosum, and occipital lobe due to right posterior cerebral artery occlusion. This rare syndrome should be considered as a "sensory" or "posterior" form of the alien hand syndrome, to be distinguished from the "motor" or "anterior" form described more commonly.  相似文献   
12.
CONCLUSION: We conclude that despite inevitable variability the clinical picture of JME is characteristic. It is easy to diagnose JME if one thinks of it while the history should be thoroughly analyzed. An EEG recording during sleep confirms the diagnosis. An early diagnosis of JME permits adequate prognosis of the subsequent course of epilepsy, and adequate therapy brings remission in most of the patients. If treatment starts following the large number of severe GTC seizures, the response to therapy is incomplete. The persistency of the illness throughout the life, the need for continuous medication and therapeutic unresponsiveness in cases with late diagnosis, do not justify the increasing misconception that JME is of benign nature. Diagnosis of JME is rare because of insufficient familiarily of physicians with the illness. BACKGROUND: Juvenile myoclonic epilepsy (JME) is an idiopathic generalized epileptic syndrome characterized with the combination of myoclonic, generalized tonic-clonic (GTC) and absence seizures that are readily provoked by sleep deprivation. PATIENTS: Forty-three patients, aged from 14 to 51 years, participated in a 5-year follow-up study. Diagnosis was made according to the criteria (Table 1) for diagnosis of JME set by Panayiotopoulos et al. (1994). Nineteen patients made their first contact with a neurologist at the Institute of Neurology and were diagnosed as JME, while the remaining 24 were referred to from other medical institutions with a diagnosis of therapy resistant to focal epilepsy. All patients underwent a somatic and neurological examination, "mini mental test," EEG in waking and CT scan of the brain. Some patients had EEG performed during sleep and some had MRI of the head. RESULTS: JME began between 9 and 26 (average 17) years. All patients had myoclonic seizures, 98% had GTC and 23% absence seizures. The first myoclonic seizure occurred between 9 and 24 years while the frst GTC seizure occurred between 10 and 32 years. Myoclonic seizures (83% of patients) and GTC seizures (70% of patients) occurred most often immediately after awaking. The most frequent provocative factors were insufficient sleep, alcohol abuse and tiredness. Epilepsy in the family was present in 39%, focal neurological deficiency in 9% and pathological findings on of CT and MRI in 7% of patients. Waking EEG was pathological in 77% of patients; it included generalized spike-wave discharges in 73%, multiple spike-wave complexes in 33% and focal discharges in 12% of patients, respectively. In all 26 patients tested, sleep EEG was pathological most often with multiple spike-wave complexes in 85% and 3-4 Hz spike-wave complexes in 57% of patients. The correct diagnosis of JME following a comprehensive examination was made in 24 (56%) patients after a delay of 1 to 35 years. In 24 patients with delayed diagnosis of JME the replacement of earlier medication with valproic acid (VPA) induced remission in 18 patients (75%) while 1 patient (4%) experienced a reduction in the number of seizures. Five patients (21%) did not respond to VPA medication: 2 due to a weak compliance, another 2 due to inefficient medication and 1 because of the preexistent malabsorption syndrome. In 19 patients (44%) with initial diagnosis of JME, VPA was introduced immediately upon diagnosis. Of them, 15 (79%) had excellent response to VPA, 1 refused therapy and for 3 patients there is no information. In 2 patients VPA was substituted due to side effects (hepatotoxicity and alopetia) with lamotrigine (low doses), which brought about decrease in frequency and mitigation in myoclonic seizures.  相似文献   
13.
Reliable methods of estimating doses are essential for the use of beta emitting radionuclides for radiotherapy. The passage of electrons through matter is a very complex phenomenon due to the large number of elastic and inelastic interactions resulting in scattering and energy losses. The analytical solution for the electron transport being intractable, the problem has been addressed by the Monte Carlo technique. Empirical or semiempirical less time consuming methods, such as the scaling factor method, may appear more preferable in practice when dealing with complicated source distributions. The method, proposed by Cross and co-workers [AECL Report Nos. AECL-1617 (1982), AECL 10521 (1992)] consists in the derivation of beta-ray dose distribution in other media from those in water by using a "scaling factor" or "relative attenuation factor" on distance and a closely related renormalization factor imposed by the energy conservation. This work investigates the accuracy of the scaling factor method using a statistical approach, a generalized chi 2 test, focusing on the particular case of potential interest, the scaling factor for water to bone. The direct comparison of the shapes of the depth dose deposition curves in the two media indicates discrepancies of less than 5% up to at least 60% of the range in bone, a depth within which 95% of the initial energy is deposited. The scaling factor derived by this method, 0.9720 +/- 0.0012, confirms the existing experimentally determined value of 0.973 +/- 1% [AECL Report No. AECL-10521 (1992)]. The accuracy of the determination is increased by almost a factor of 10. A way of improving the scaling method, especially for depth over the 60% continuous slowing down approximation range, by using a modulation function is also proposed.  相似文献   
14.
Heat shock proteins (HSPs) or stress proteins are synthesized by cells in response to environmental stress. Expression of HSPs by cells may have important physiological or pathological implications. In this study, we carried out an immunohistochemical and biochemical examination of low (hsp27), intermediate (hsp60), and high (hsp89) molecular weight HSP expression in reactive lymph nodes and in lymph nodes of patients with various types of lymphomas. In normal or reactive lymphoid tissues, hsp89 is abundant in large "transformed" lymphoid cells and immunoblasts. Hsp60 is widely distributed in lymphoid tissues, whereas hsp27 is absent in all lymphoid cells and histiocytes. Among lymphomas, the Hodgkin's Reed-Sternberg (H-RS) cells in Hodgkin's disease (HD) had the greatest abundance of hsp89 and hsp60 and, in 20% of cases, hsp27, in contrast to a much weaker staining of anti-hsp89 and -hsp60 in the background reactive lymphoid cells. The large lymphoid cells in small lymphocytic lymphoma are also rich in hsp89, but not hsp60 and hsp27. In contrast, the malignant cells in anaplastic large cell lymphoma and most high-grade tumors, including immunoblastic lymphomas, expressed minimal amounts of hsp89 and hsp60 and virtually no hsp27. Thus, the cellular level of HSPs was neither correlated with the proliferative capacity nor with the aggressiveness of the lymphomas. Hsp89, hsp60, and hsp27, as well, serve critical roles in the chaperoning of cellular proteins (e.g., a Mr 43,000 protein) in H-RS cells. The known interactions of HSPs with Rb, p53, peptide-MHC class II complexes, and cofactors of the glucocorticoid hormone receptor have further broadened the importance of HSPs in cell metabolism and in response to extracellular signals for proliferation, differentiation, or growth suppression (or apoptosis) of H-RS cells. Abundant HSP expression is seen only in HD, but not in other lymphomas. Such expression could have vital roles in the pathogenesis of HD.  相似文献   
15.
The heavy chain of cytoplasmic dynein is required for nuclear migration in Aspergillus nidulans and other fungi. Here we report on a new gene required for nuclear migration, nudG, which encodes a homologue of the "8-kD" cytoplasmic dynein light chain (CDLC). We demonstrate that the temperature sensitive nudG8 mutation inhibits nuclear migration and growth at restrictive temperature. This mutation also inhibits asexual and sexual sporulation, decreases the intracellular concentration of the nudG CDLC protein and causes the cytoplasmic dynein heavy chain to be absent from the mycelial tip, where it is normally located in wild-type mycelia. Coimmunoprecipitation experiments with antibodies against the cytoplasmic dynein heavy chain (CDHC) and the nudG CDLC demonstrated that some fraction of the cytoplasmic dynein light chain is in a protein complex with the CDHC. Sucrose gradient sedimentation analysis, however, showed that not all of the NUDG protein is complexed with the heavy chain. A double mutant carrying a cytoplasmic dynein heavy chain deletion plus a temperature-sensitive nudG mutation grew no more slowly at restrictive temperature than a strain with only the CDHC deletion. This result demonstrates that the effect of the nudG mutation on nuclear migration and growth is mediated through an interaction with the CDHC rather than with some other molecule (e.g., myosin-V) with which the 8-kD CDLC might theoretically interact.  相似文献   
16.
Though blending polymers to obtain high performance materials is an old practice, the new trend in such an approach is the emergence of interpenetrating polymer networks (IPNs) as binders for protective coatings with improved properties. In this study, one ambient curing IPN-type polymer alloy developed out of epoxy and acrylic polyurethane systems as a high performing binder was formulated into paints and evaluated in comparison with the currently used conventional epoxy polyamide and polyurethane systems. A three-coat system consisting of a zinc phosphate primer, a micaceous iron oxide (MIO) undercoat, and a topcoat was formulated out of the IPN along with a similar system of epoxy primer, epoxy undercoat, and a PU topcoat. A two-coat system of the same primer with an IPN clear topcoat and a similar system with epoxy has also been studied. All the systems were studied under accelerated laboratory tests and field tests at a corrosive location. The results are reported and conclusions are drawn in this article. An erratum to this article can be found at  相似文献   
17.
The NMR solution structure of an immunoglobulin superfamily module of twitchin (Ig 18') has been determined and the kinetic and equilibrium folding behaviour characterised. Thirty molecular coordinates were calculated using a hybrid distance geometry-simulated annealing protocol based on 1207 distance and 48 dihedral restraints. The atomic rms distributions about the mean coordinate for the ensemble of structures is 0.55( +/- 0.09) A for backbone atoms and 1.10( +/- 0.08) A for all heavy atoms. The protein has a topology very similar to that of telokin and the titin Ig domains and thus it falls into the I set of the immunoglobulin superfamily. The close agreement between the predicted and observed structures of Ig 18' demonstrates clearly that the I set profile can be applied in the structure prediction of immunoglobulin-like domains of diverse modular proteins. Folding studies reveal that the protein has relatively low thermodynamic stability, deltaG(H2O)U-F = 4.0 kcal mol(-1) at physiological pH. Unfolding studies suggest that the protein has considerable kinetic stability, the half life of the unfolding is greater than 40 minutes in the absence of denaturant.  相似文献   
18.
The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data.  相似文献   
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